ˌtōbrəˈmīs ə n noun
( -s )
Etymology: tobra- (probably modification of New Latin tenebrarius , specific epithet of Streptomyces tenebrarius ) + -mycin
: a water-soluble antibiotic C 18 H 37 N 5 O 9 derived from a soil bacterium of the genus Streptomyces ( S. tenebrarius ) and effective especially against gram-negative bacteria